Transcript Third-Generation Database System manifesto

Third-Generation Database
System manifesto
The committee for advanced
Database Management System
(DBMS) Function
Question:
What is the path we must follow to
arrive at the next generation of
DBMS?
Current state description
from authors (1990)
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Mainly 2nd generation DBMS
Agreement in industry that the current DBMS
need extended capabilities.
There is a need for getting the common
understanding of where we are going down on
the paper.
A counterweight to the spreading objectoriented enthusiasm is needed.
What is needed:
A gradual transition from 2nd
generation DBMS to a 3rd
generation DBMS
First Tenet
Besides traditional database management
services, third generation DBMSs will
provide support for richer object structures
and rules
Second Tenet
Third generation DBMSs must subsume
second generation DBMS.
Third Tenet
Third generation DBMSs must be open to
other subsystems.
(1. Tenet)
Object and Rule Management
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A rich type system is needed (including
extensions to query language).
(Multiple- ) Inheritance is a good idea.
Functions, including database procedures and
methods, and encapsulation are a good idea.
Unique IDs should only be reassigned if
human defined primary key is not available.
Rules are important.
(2. Tenet)
Increasing DBMS Function
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Programmatic access should be through a nonprocedural high-level access language
(minimal navigation).
Collections should be definable both through
member enumeration and through queries
(extensionally vs. intentionally).
Updatable views are essential.
Performance indicators must not appear in data
models.
(3. Tenet)
Need for an open system.
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DBMSs must be accessible through multiple
higher level languages.
Persistent objects is a good idea.
SQL will prevail.
Queries and result set should be the lowest
level of communication.
Needed improvements in current
DBMS to become 3rd generation
DBMS
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Improvements in relational databases systems:
inheritance and additional type constructors.
Improvements in object-oriented database
systems: query language, query optimizers,
views and SQL support.
Both database systems need support for
persistent programming languages.
Conclusion
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Object-oriented databases is not the solution to
the challenges found in using 2nd generation
DBMSs.
The existing experience and expertise built
into the existing relational databases should be
used as much as possible.
Development based on the current 2nd
generation DBMS is more sensible than new
development from scratch.